[SchildiChat] Matrix Webclient

I packaged SchildiChat. If feedback and testing greatly appreciated!

I based my work off of GitHub - YunoHost-Apps/element_ynh: Element package for YunoHost because SchildiChat is a fork of Element.

My Repository can be found here: GitHub - benjaminwolkchen/schildichat_ynh: SchildiChat Package for YunoHost